This invention relates in general to surgical instruments and in particular to an improved structure for a gripper for trocars used in laparoscopic surgical procedures, and a plug for use therewith which facilitates suturing of laparoscopic surgery puncture wounds.
Trocars are sharp-pointed instruments used to puncture a body cavity. This is often done so that fluids may be drained using a tube inserted into the opening. Trocars are also used in laparoscopic surgery. Laparoscopic surgery is a relatively new operating technique which involves puncturing the abdominal wall, and then performing the surgery through the relatively small opening of the puncture. This technique is much less invasive than conventional surgery in which the surgery is performed through a relatively large incision through the abdominal wall.
Before puncturing the abdominal wall, an inert gas, such as carbon dioxide, is introduced within the abdominal cavity, usually by means of a needle supplied with the inert gas from a pressurized source. The introduction of the inert gas expands the abdomen to facilitate access to the body parts requiring surgery and visual observation of the procedure.
Trocars used in laparoscopic surgery generally include a stylet having a sharp tip for penetrating through a patient's abdominal wall and a hollow trocar guide tube having smooth internal and external surfaces. Prior to user the trocar stylet is inserted into the trocar guide tube. After the abdomen has been expanded by introduction of the inert gas, the trocar is used to puncture the abdominal wall. Typically, a small incision is made in the skin at a selected site, using a scalpel. The sharp point of the stylet is inserted into the incision, and then pressed through the abdominal wall. After the trocar has punctured the abdominal wall, the stylet is removed, leaving the trocar guide tube extending through the abdominal wall. A variety of surgical instruments may then be inserted through the trocar guide tube to perform the surgery within the abdomen.
As indicated above, the trocar guide tube typically has a smooth external surface so that it will slide relatively easily into the puncture. However, the smooth surface does not grip the abdominal wall well once it has been inserted. Therefore the trocar guide tube may be accidentally pulled out of the puncture during removal of surgical instruments, or may be expelled by gas pressure within the abdomen. A gripper is therefore commonly used to hold the trocar guide tube in position relative to the abdominal wall.
One general type of gripper which is known is a hollow cylindrical device which has an external helical thread and structure for releasably gripping an associated trocar guide tube. The trocar guide tube is inserted into the gripper before the trocar is used to puncture the abdominal wall. After the trocar has penetrated the abdominal wall, the gripper is slid down the trocar guide tube into contact with the abdominal wall. The gripper is then rotated to thread the gripper into the abdominal wall, fixing the gripper against axial movement. The gripping structure is then operated to secure the trocar guide tube against axial movement within the gripper.
As indicated above, laparoscopic surgery is much less invasive than conventional surgical techniques, and much smaller openings are made through the abdominal wall. It had been thought, up to now, that the puncture wounds thus created did not need to be sutured to heal properly, given their relatively small size. Nevertheless, it has been found that the punctures made through the abdominal wall, particularly of the larger diameter trocars, sometimes do not close properly. Wound closure of the fascia layer or layers of the abdominal wall is especially important. Without proper wound closure, hernias can develop at these sites when portions of internal organs, notably bowel, protrude through the wound. However, the relatively small size of the wound makes suturing of the fascia using conventional suturing techniques difficult. Therefore, an apparatus that facilitates the suturing of puncture wounds resulting from laparoscopic surgery, thus facilitating wound closure, would be desirable.